There is an increasing need to reduce energy consumption to tackle the adverse effects of climate change. The UK government has established numerous directives and policies to encourage carbon dioxide (CO2) emission and energy reduction within the non-domestic sector. However these measures are primarily focused towards reducing operational energy (i.e. energy used during building occupier activity), largely overlooking initial embodied energy. The trend towards reduced operational energy consumption due to energy efficient design is leading initial embodied energy to become a more significant part of project life cycle energy. Initial embodied energy relates to the energy use during the material, transportation and construction phases up to project practical completion, which is of keen interest to contractors due to their significant role in project procurement and delivery.
Opportunities to address project life cycle energy are typically identified through a Life Cycle Assessment (LCA). However at present there is little validated data, no coherent method for data capture and limited incentive for project stakeholders to address initial embodied energy consumption. In response, this research project presents a contractor s practical approach towards assessing initial embodied energy consumption within UK non-domestic construction projects. An action research methodological approach enabled the assessment and potential reduction of initial embodied energy to be explored within a large principal contractor through five research cycles which included diagnosing and action planning, action taking, evaluating and specified learning.
A comprehensive framework is designed to highlight the significance of initial embodied energy consumption relative to specific construction packages, activities and sub-contractors. This framework is then explored within three UK non-domestic construction projects (i.e. two industrial warehouses and one commercial office). Capturing information from live projects enables practical challenges and opportunities inherent when addressing initial embodied energy consumption to be identified. A series of contractor current practices are reviewed, and subsequently improved, to enhance their compliance with the framework requirements.
The findings emphasise the importance of material phase impacts, especially construction packages which primarily contain steel and concrete-based materials (i.e. ground and upper floor, external slab and frame). The importance of project type, site area, building lifespan and waste consumption are also recognised to reduce initial embodied energy consumption. The framework provides a practical approach for initial embodied energy assessment which can readily be adopted to help highlight further opportunities to reduce energy consumption. The research project concludes by presenting a number of recommendations for consideration by the construction industry and associated stakeholders, along with requirements for future research.

Description:

A dissertation thesis submitted in partial fulfilment of the requirements for the award of the
degree Doctor of Engineering (EngD), at Loughborough University